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The rhizosphere microbiota plays a critical and crucial role in plant health and growth, assisting plants in resisting adverse stresses, including soil salinity. Plastic film mulching is an important method to adjust soil properties and improve crop yield, especially in saline–alkali soil. However, it remains unclear whether and to what extent the association between these improvements and rhizosphere microbiota exists. Here, from a field survey and a greenhouse mesocosm experiment, we found that mulching plastic films on saline–alkali soil can promote the growth of soybeans in the field. Results of the greenhouse experiment showed that soybeans grew better in unsterilized saline–alkali soil than in sterilized saline–alkali soil under plastic film mulching. By detecting the variations in soil properties and analyzing the high-throughput sequencing data, we found that with the effect of film mulching, soil moisture content was effectively maintained, soil salinity was obviously reduced, and rhizosphere bacterial and fungal communities were significantly changed. Ulteriorly, correlation analysis methods were applied. The optimization of soil properties ameliorated the survival conditions of soil microbes and promoted the increase in relative abundance of potential beneficial microorganisms, contributing to the growth of soybeans. Furthermore, the classification of potential key rhizosphere microbial OTUs were identified. In summary, our study suggests the important influence of soil properties as drivers on the alteration of rhizosphere microbial communities and indicates the important role of rhizosphere microbiota in promoting plant performance in saline–alkali soil under plastic film mulching. [ABSTRACT FROM AUTHOR]

Summary: Recombination is crucial for crop breeding because it can break linkage drag and generate novel allele combinations. However, the high‐resolution recombination landscape and its driving forces in soybean are largely unknown. Here, we constructed eight recombinant inbred line (RIL) populations and genotyped individual lines using the high‐density 600K SoySNP array, which yielded a high‐resolution recombination map with 5636 recombination sites at a resolution of 1.37 kb. The recombination rate was negatively correlated with transposable element density and GC content but positively correlated with gene density. Interestingly, we found that meiotic recombination was enriched at the promoters of active genes. Further investigations revealed that chromatin accessibility and active epigenetic modifications promoted recombination. Our findings provide important insights into the control of homologous recombination and thus will increase our ability to accelerate soybean breeding by manipulating meiotic recombination rate. [ABSTRACT FROM AUTHOR]

Farmland irrigation is an essential foundation for good crop growth, while traditional farmland irrigation techniques cannot fully consider the impact of factors such as natural precipitation and crop transpiration on crop growth, which can, to a certain extent, result in poor irrigation decisions and a complex farmland environment that cannot be monitored promptly, thereby reducing farmland production efficiency. This study designs a farmland irrigation control system based on a composite controller. Firstly, an irrigation control method is proposed to establish a prediction model for future rainfall and crop transpiration using historical meteorological data. The composite controller is designed based on the prediction model to realize an irrigation control operation with an irrigation value as the control quantity, a water and fertilizer machine, and a solenoid valve as the actuators. Secondly, an intelligent irrigation control cloud platform based on Java language is designed to monitor farm information and irrigation operation records in real-time to facilitate visual management. Finally, the prediction accuracy is high, based on the prediction model results, which can provide a specific reference basis. The superiority of the proposed controller is verified by simulation using MATLAB/Simulink. The results show that the proposed controller can be well suited for nonlinear control systems and has good control performance while ensuring high tracking accuracy, strong robustness, and fast convergence. [ABSTRACT FROM AUTHOR]

The sugarcane lifting–cutting System (SLS) is the core component of the sugarcane harvester, and the influence of its stalk lifting height on the mechanism of perennial root-cutting damage is still unclear. The test was conducted with the vertical height of centroid (VHC), forward velocity, and cutter rotational speed. Numerical quantification of perennial root based on the cutting breakage effect and cutting breakage grade (CBG) classification was used as the evaluation index. The test results showed that the VHC had a highly significant effect on the CBG of the perennial root. The CBG of the stalk decreased significantly with the lifting height. The average CBG was greater than 2.0 when the stalk lifting height was severely collapsed. The CBG ≤ 1.6 was considered qualified, and the requirements were met when the VHC of the stalk was about 0.85~1.0 m at a forward velocity of 1~3 km/h. The inverted angle of the stalk being lifted was selected to be 45° as the evaluation standard to measure the qualified lifting of the spiral sugarcane lifter. This study provides technical support for the optimal design and selection of operating parameters of the sugarcane harvester. [ABSTRACT FROM AUTHOR]

Summary: Seed size is one of the most important agronomic traits determining the yield of crops. Cloning the key genes controlling seed size and pyramiding their elite alleles will facilitate yield improvement. To date, few genes controlling seed size have been identified in soybean, a major crop that provides half of the plant oil and one quarter of the plant protein globally. Here, through a genome‐wide association study of over 1800 soybean accessions, we determined that natural allelic variation at GmST05 (Seed Thickness 05) predominantly controlled seed thickness and size in soybean germplasm. Further analyses suggested that the two major haplotypes of GmST05 differed significantly at the transcriptional level. Transgenic experiments demonstrated that GmST05 positively regulated seed size and influenced oil and protein contents, possibly by regulating the transcription of GmSWEET10a. Population genetic diversity analysis suggested that allelic variations of GmST05 were selected during geographical differentiation but have not been fixed. In summary, natural variation in GmST05 determines transcription levels and influences seed size and quality in soybean, making it an important gene resource for soybean molecular breeding. [ABSTRACT FROM AUTHOR]

Elastocaloric refrigeration requires refrigerants with a good heat transfer ability and a high fatigue life. A million-level fatigue life can be normally obtained for NiTi refrigerants via compressive loading. However, existing compression-based NiTi elastocaloric prototypes only focus on tube refrigerants, and no research has been reported on the cross-sectional geometry design and its influence on the compression fatigue behavior of NiTi refrigerants. Here, we propose tubular NiTi refrigerants of hole-type, fin-type, and layer-type cross sections and compare their compression fatigue behavior with NiTi tubes of the same cross-sectional area under cyclic loading of 20 Hz and 900 MPa. Results show that to achieve a larger specific heat transfer area (SA), the compression fatigue life of NiTi tubes monotonically decreases because of the decrease in the wall-thickness, while the layer-type NiTi refrigerant maintains a relatively high fatigue life of 1.7 × 106 cycles at a high SA level (3.83 cm2 g−1). This gives us insight into enhancing elastocaloric refrigerants' heat transfer ability and fatigue life via geometry design. [ABSTRACT FROM AUTHOR]

The traditional fertilizer application methods have serious problems of environmental pollution and soil degradation due to low utilization rates in the Huang–Huai–Hai Plain of China. In this study, the conservation tillage strip-hole layered fertilization method was proposed and a precision strip-hole layered fertilizer subsoiler was designed. To meet the requirements for deep tillage strip-hole layered fertilizer application, theoretical analysis and parameter calculations were first carried out on the fertilizer application type hole wheel, and then the main factors affecting the fertilizer application effect of a strip-hole layered fertilizer shovel were analyzed. The effect of forwarding speed, angle of fertilizer tube installation (AFT) and angle of unloading fertilizer (AUF) on the middle and lower layers of the fertilizer distribution length (FDT) and fertilization amount deviation stability coefficient (FADSC) was studied using the discrete element method (DEM). The three-factor three-level full-factors test design method was adopted. Simulation results showed that the FDT and the FADSC increased as the forward speed increased; the FDT decreased as the AFT and the AUF increased; an increased FADSC was observed at a middle angle of the AFT and the AUF. The minimum FADSC was obtained for a combination of parameters with a forward speed of 2 km/h, the AFT of 35° and the AUF of 60°, corresponding to the FADSC of 2.49% in the middle layer and 2.93% in the lower layer while satisfying the FDT condition. The results of the field trials showed that the FADSC was 11.36% and 12.42%, respectively, an increase of 8.87% and 9.49%, respectively, compared to the simulation results, validating the simulation model. The new way of fertilizer application methods and a theoretical basis were provided for the design of hole application machinery. [ABSTRACT FROM AUTHOR]

This paper introduces a new cleaner emulsion‐explosive formula and uses it in the copper/aluminum parallel plates explosive welding, with the benefits of decreasing the overall cost of emulsion explosive product and minimizing environmental pollution during use. After the welding experiment, sample's welding quality was firstly evaluated via the X‐ray tomography (XCT), optical microscopy (OM) and scanning electron microscopy (SEM). On the other hand, the energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM) and X‐ray diffraction (XRD) analysis are utilized to identify the kinds of inter‐metallic compounds of samples. Our results reveal that the metal/metal interface obtained using the new emulsion explosive is more regular and wavy, and the inter‐metallic compounds, caused by rapid solidification and further cooling of the dissimilar partners, are confirmed as Al2Cu and AlCu. [ABSTRACT FROM AUTHOR]

Abstract: This paper introduces a novel emulsion explosive, which has three primary advantages, namely, the ability to easily adjust various detonation properties to desired values, decrease the overall cost of civil explosive products, and minimize environmental pollution during use. Immediate and time‐related experiments are performed in order to identify changing detonation properties of these new formulas. Our results show that both common clay and hollow glass micro‐spheres (HGMs) function as thermal diluents, which indicates that for a larger quantity of these additives, the weaker are the detonation properties under the condition of our experimental ratios (HGMs: from 5 wt.% to 15 wt.%; common clay: from 0 wt.% to 20 wt.%). Furthermore, a comparison of four alternative emulsion explosive compositions reveals that the longest storage time in this study is 5 weeks with No. 3‐3, which contains 15 wt.% HGMs and 10 wt.% common clay. In addition, nonlinear attenuation is observed and explained for that period. [ABSTRACT FROM AUTHOR]

Na+/H+ antiporters have been well documented to enhance plant salt tolerance by regulating cellular ion homeostasis. Here, a putative Na+/H+ antiporter gene homolog GmNHX2 from soybean was cloned and predicted to encode a protein of 534 amino acids with 10 putative transmembrane domains. GmNHX2 was expressed in all soybean plant tissues but enriched in roots and its expression was induced by NaCl and polyethylene glycol (PEG) treatments. GmNHX2 exhibits greater sequence similarity with LeNHX2 and AtNHX6 than that of AtNHX1 and AtSOS1. Although phylogenetic analysis clustered GmNHX2 with organellar (tonoplast and vesicles) antiporters, the GmNHX2-EGFP (enhanced green fluorescent protein) fusion protein was possibly localized in the plasma membrane or organelle membrane of transgenic plant cells. Furthermore, transgenic Arabidopsis plants expressing GmNHX2 were more tolerant to high NaCl concentrations during germination and seedling stages when compared with wild-type plants. These results suggest that GmNHX2 is a membrane Na+/H+ antiporter and may function to regulate ion homeostasis under salt stress. [ABSTRACT FROM AUTHOR]

As a critical component of the sugarcane harvester, the primary function of the crop dividers is to lift the lodged sugarcane (LS) and reduce the loss rate of the sugarcane harvest. In this study, a rigid-flexible coupling simulation method is proposed to improve the lifting efficiency of the crop dividers on severely LS and analyze the nature of interaction between the sugarcane stalk and the crop dividers. The model's accuracy was verified using field experiments, and the operational performance of the crop dividers on sugarcane in different lodging postures was investigated. The results showed that the curve of the vertical height of the center (VHC) fluctuated more and slipped with highest frequency during the lifting process of side and forward LS. The speed of VHC was fastest during the lifting operation of side LS. The effect of side angle on the lifting effect of sugarcane was significant; the qualified values of the VHC of sugarcane being lifted in different lodged postures were: side and reverse lodged > side lodged > side and forward lodged. The coupling method and experimental results described in this paper can provide guidance for the optimal design and field operation of the crop dividers. [ABSTRACT FROM AUTHOR]

RNA editing plays a key role in organelle gene expression. Little is known about how RNA editing factors influence soybean plant development. Here, we report the isolation and characterization of a soybean yl (yellow leaf) mutant. The yl plants showed decreased chlorophyll accumulation, lower PS II activity, an impaired net photosynthesis rate, and an altered chloroplast ultrastructure. Fine mapping of YL uncovered a point mutation in Glyma.20G187000, which encodes a chloroplast-localized protein homologous to Arabidopsis thaliana (Arabidopsis) ORRM1. YL is mainly expressed in trifoliate leaves, and its deficiency affects the editing of multiple chloroplast RNA sites, leading to inferior photosynthesis in soybean. Taken together, these results demonstrate the importance of the soybean YL protein in chloroplast RNA editing and photosynthesis. [ABSTRACT FROM AUTHOR]

Background: Soybean (Glycine max [L.] Merr.) is one of the most important oil and protein crops. Ever-increasing soybean consumption necessitates the improvement of varieties for more efficient production. However, both correlations among different traits and genetic interactions among genes that affect a single trait pose a challenge to soybean breeding., Results: To understand the genetic networks underlying phenotypic correlations, we collected 809 soybean accessions worldwide and phenotyped them for two years at three locations for 84 agronomic traits. Genome-wide association studies identified 245 significant genetic loci, among which 95 genetically interacted with other loci. We determined that 14 oil synthesis-related genes are responsible for fatty acid accumulation in soybean and function in line with an additive model. Network analyses demonstrated that 51 traits could be linked through the linkage disequilibrium of 115 associated loci and these links reflect phenotypic correlations. We revealed that 23 loci, including the known Dt1, E2, E1, Ln, Dt2, Fan, and Fap loci, as well as 16 undefined associated loci, have pleiotropic effects on different traits., Conclusions: This study provides insights into the genetic correlation among complex traits and will facilitate future soybean functional studies and breeding through molecular design.